1. Field of the Invention
The present invention relates to a method of maintenance of an ordinary structure such as a house, a bridge, a gravestone, a fence, a guard rail or a building through cleaning of a stain caused by molds and dust adhering to the surface thereof.
More particularly, the present invention relates to a method of maintenance through cleaning of a surface of a wooden outer wall, a wood block, a stone-built construction, a concrete structure, a tile, a slate, a glass plate, a roofing tile, plastics, mortar, an steel plate, etc. constituting the above-mentioned various structures.
Further, the invention relates to a method of maintenance of a structure such as a road or a road tunnel through improvement of permeability of rainwater falling onto a motorway for traffic of various motor vehicles and onto a footway for passage of general pedestrians, through cleaning a stain adhering to the road surface, etc.
More specifically, the invention relates to a method of maintenance for constantly keeping water permeability and drainage on a satisfactory level through prevention of frost of rainwater having entered voids of a porous material forming the surface course of a permeably paved road, or through removal of clogging caused by fine dust occurring from wear of tires of a running automobile or sand and dust contained in the air, coming into voids of pavement formed by a porous material.
2. Description of the Related Art
It has been the conventional practice of maintenance of a structure such as a building and a paved road to spray an organic solvent or an organic chemical detrimental to human health onto a stain on the surface of a surface to be cleaned, or polish or grind the same with a mechanical cleaning tool by a cleaning operator.
This method of maintenance, requiring a long period of time from the start of spraying of the organic solvent or the organic chemical, or from the start of polishing or grinding until the end of cleaning, is low in efficiency. Further, side effects and an offensive odor of the solvent or the chemical, and scattering of fine dust may result in deterioration of sanitary environments not only for cleaning operators, but also for inhabitants living near the site or for flora and fauna.
As a result, the cleaning operators, the inhabitants in the neighborhood of the site, and flora and fauna are exposed to a serious risk caused by the organic solvent, the organic chemical and the mechanical tools.
Maintenance such as cleaning of a permeable road or a drainage-type road has conventionally been accomplished mechanically by use of various mechanical cleaning devices such as a sweeping truck, a high-pressure cleaner, a brush and a vacuum truck to remove a stain adhering to the road surface.
For the purpose of preventing frost of rainwater staying on the road surface and rainwater coming into voids of the surface course thereof in winter, it is the common practice to sprinkle an aqueous solution of one or more salts selected from calcium chloride, magnesium chloride and sodium chloride in large quantities onto the road surface for thawing.
An object of the present invention is to improve sanitary environment without exerting an adverse effect on health of cleaning operators and inhabitants living near the site while avoiding inefficient cleaning operation including spraying of an organic chemical detrimental to human health and polishing with a mechanical cleaning tool employed in the conventional cleaning method.
Another object of the invention is to permit avoidance of direct touch of hands with the dirt or of a difficult or dangerous work, hated by cleaning operators.
Still another object of the invention is to avoid the necessity of mechanical cleaning tools as compared with the conventional mechanical cleaning of a road with various mechanical cleaning tools.
A further object of the invention is to prevent an aqueous solution of the salts as mentioned above from causing a salt damage to running vehicles, a river, a house or a plant near the road as compared with the method of maintenance of sprinkling the solution of the aforementioned salts in large quantities onto the road surface.